1. Field of the Invention
The present invention relates to hot aisle/cold aisle containment systems. In particular, it relates to improvements in floor panel design for narrowing the width of cold isles in data centers.
2. Description of the Related Art
Raised floors are used in data centers to create a space between a sub-floor of the building and the normal working environment of the computer room. The space between the sub-floor and the raised floor panels creates an under-floor cool-air circulating plenum for thermal management of the data processing servers installed in banks of rack systems on top of the raised floor. The floor panels, themselves, are either solid or perforated. The solid panels are typically used for supporting a heavy or rolling load. Of the perforated panels, manufacturers have made new design changes in an effort to increase the available open area of the panels, in order to increase the air flow of cooling air throughout the room. These efforts have led to the production and use of air-grate raised floor panels.
A further refinement, in the use of air-grate floor panels, came in the early 2000s, when scientists advanced the concept of “hot aisle/cold aisle”, as an additional means for attempting to achieve air separation within the server room. This design includes three basic components to achieve hot aisle/cold aisle separation. Those components involve the use of air conditioners, fans and perforated raised floor panels, in combination, to act synergistically in the construction of a cooling infrastructure, as a means to separate and contain the inlet cold air and the exhaust hot air. With this approach, the cabinets are supported on a raised floor and are connected into a series of rows. The fronts of the racks face each other and become the cold aisles, as a result of the inherent front-to-back heat dissipation of most IT equipment. The air conditioning units are positioned around the perimeter of the room, or at the end of hot-aisles, so that they push cold air under the raised floor and through the cold aisle. The perforated raised floor panels are placed only in the cold aisles which concentrates cool air to the front of racks in order to get sufficient air flow into the server intake. In this manner, all of the servers should be mounted so that their server door air intake is facing the front of the rack, and their exhaust door is facing the rear. As the air moves through the servers, it is heated and eventually dissipated into the hot aisle. The exhaust air is then routed back to the air handlers.
This design, which aligns data center cabinets into alternating rows, endures in critical facilities throughout the world, and is widely regarded as the first major step in improving airflow management. In use, part of this air flow, or stream, enters the racks and then the equipment, and part of the air flow bypasses the equipment and returns to the air handling units. The air that enters the server doors is heated, and then exhausted through the back of the servers where it is recycled as return air into the air handling units. Typically, some intermixing of the hot and cold air paths is experienced due to improper sealing in the rack, or recirculation above and around the sides of the rack rows. The air-grate panels include perforated top plates, connected to the air-grate structural frame members, in order to provide a variety of different working surfaces having a desired aesthetic appearance, or with the perforations, or openings, in the plate configured so as comply with certain federal and state regulations, as they relate to occupational safety and/or persons with disabilities, or to increase air flow and cooling efficiency.
The Accessibility Guidelines of the Americans with Disabilities Act (“ADA”) sets forth minimum standard requirements for accessibility in public places. In application, these requirements effectively regulate an approximately 91 centimeters, or 3 foot, minimum width requirement which is available for use in the construction of cold aisles between rows of server racks. However, this mandate is inconsistent with the 61 cm×61 cm on center square geometry of those raised floor pedestal support systems which have gained universal acceptance in the industry. There, the cold aisle is created by installing two adjacent rows of 61 cm×61 cm on center air-grate panels and supporting the server racks with rows of rows of 61 cm×61 cm solid surfaced panels. It follows that the universally accepted cold aisle construction is thereby approximately 122 cm, or 4 feet wide, which is approximately 30.5 cm, or one foot, greater than the minimum mandated under the ADA. Thus, because of the square geometry of the universally accepted raised floor systems in accordance with the prior art, in order to comply with the ADA regulations, one must either purchase more total surface area to construct a facility having a predetermined data processing capacity, or must effectively reduce the concentration of server units within an existing surface area for use in data processing.
One such solution has heretofore been to provide rectangular air-grate floor panels, configured with a dimension of approximately 61 cm×91 cm, for cold-aisle specific installation. While this installation will effectively narrow the cold aisle and eliminate the 30.5 cm of unused space, it is somewhat impractical, because it inherently requires one to make corresponding changes to the 61 cm×61 cm on center configuration of new or existing the pedestal support systems at the cold aisle, so that it is capable of supporting the cold aisle specific rectangular panels. Altering the square geometry of the pedestal support members, so that they are capable of supporting the cold aisle specific rectangular air-grate floor panels complicates any subsequent rearrangement or replacement of the floor panels, the rows or server racks, or with new or existing panels of differing manufacture.
Thus, what is needed is an interchangeable raised floor access panel which is compatible for use with the existing 61 cm×61 cm on center pedestal support systems, but which is also capable of installation in the formation of a cold aisle which is narrowed to the mandatory minimum, 91 cm, width. The present invention satisfies these needs.